Spanish writer and musician remembered chiefly for his picaresque novel La vida del Escudero Marcos de Obregón (1618; “Life of Squire Marcos of Obregón”), upon which the French novelist Alain-René Lesage based parts of his Histoire de Gil Blas de Santillane (1715–35; The History of Gil Blas of Santillane).

After his expulsion from the University of Salamanca in 1572, Espinel entered the army and led a roguish life very much like that of his character Marcos, visiting Italy, Flanders, and the Netherlands. He returned to Spain in 1584 and was ordained to the priesthood in 1587. Espinel revived the décima, an octosyllabic 10-line stanza that became widely used in Spanish verse in a form known as the espinela. Espinel was also once mistakenly thought to have added the fifth string to the Spanish guitar.